Private vs. public vs. hybrid Cloud

August 21, 2017

Because of this interesting article written by Cumulus Networks I decided to think about some questions regarded to this topic. Below you can read my personal thougths about the different kinds of a cloud. Some information are out of the mentioned article.

My definition of a Cloud

A cloud is a bunch of computing systems which together build a closed system that provides computing, networking, storage, security, applications and services. People or other computer systems can make use of this things in an automated manner, use them on demand as single parts or combine them to get a fully working system. The key point for the following differentiations is the surface where the resources are offered: in your own infrastructure/data-center (private), in the internet (public) or both (hybrid).


source: tek-nologysolutions

The correct choice?

Todays companies have to decide where to run their applications. Build a private cloud? Use a public cloud? Do both? Which is the best for my applications? Who wants to use them? What is needed? SaaS? Or only a pool of resources? All these questions require a very good planning and oversight. Each application can be different. But the important thing is: the application has to run with focus-first to the customers/users. The decision how to run applications and IT systems should be driven by the needs of customers/users. Whats the purpose of the best-running private cloud or the perfect network solution if in the end none of the end users can profit of it? If this happens something went wrong and a lot of unnecessary expense were generated.

Public Cloud

Public Clouds are hosted and maintained by an external provider. Some of the biggest are Microsoft Azure, Google Cloud Platform or Amazon AWS. Such big clouds are separated into a tenant per customer. So every customer gets some pieces of computer resources which are logically reserved and only available for him. How much resources you get depends on how much you are willing to pay for.

The big benefit of public clouds is the fact that you can fully concentrate on your application. The things in behind are maintained and run by the cloud provider. If something fails you can open tickets or the provider has some self-healing/failover mechanisms. But don`t forget that you still have to administrate the cloud and to understand how the cloud provider works. If this approach fits for your application a public cloud could be a good choice and can lead to time and money savings.

Private Cloud

Private Clouds run in own environments/datacenters: on-premise. They can be configured to support any needs of your applications in the best possible manner. You have full control over the cloud and can use whatever you want to build it. Often it is a high barrier of planning and beginning such a project. But if you have the people and knowledge in your company in most cases it is a very good choice to build and run a private cloud. The cloud can offer everything your people and customers need.

Another key point is that you know where your applications are running. You don`t have to think about a lot of compliance topics. Does it for example make a difference if my company data is stored on a system in Europe or the USA?

Hybrid Cloud

With Hybrid Cloud solutions you can get the best out of both worlds. Use the cloud you need at the moment! You have a legacy application? Go for your private cloud. You want to use an application which perfectly runs on AWS or even better is fully integrated and available there? Choose AWS. You need a Microsoft Sharepoint test environment? Choose Azure.

Of course a hard point of this approach is again the compliance. Now you have to consider not only one cloud-environment, but rather two, three or more. And you have to know the guidelines and specifics of each of them. So in sum a hybrid approach usually leads to the most overhead of resources and management.

Benefits of moving to a private cloud

The following points are referenced from the mentioned article of Cumulus Networks.

  • cost efficiency
  • improved security (“single tenant”)
  • web-scale IT agility and continuity
  • resource optimization (no vendor locking)
  • greater control
  • more customization
  • less compliance issues
  • unlimited scalability and adaptability

The following points are referenced from the mentioned article of Cumulus Networks.

  • devops and netdevops
  • hyper-converged infrastructure
  • disaggregation (e.g. with Cumulus Linux)